This invention relates to a rotary internal combustion engine and, more particularly, to a stratified charge natural gas rotary internal combustion engine.
Rotary combustion engines generally burn gasoline or diesel-type fuels which are liquid at normal pressures and temperatures. A rotary combustion engine for burning gaseous type fuels is described in U.S. Pat. No. 3,886,907, wherein a natural gas side intake port is positioned so that there is no overlap of the gas intake with the exhaust port and so that the gas intake closes before the air intake closes. Another proposed design for a natural gas rotary engine is described in SAE Technical Paper 850034, "Development of a Natural Gas Stratified Charge Rotary Engine" by Sierens and Verdonck. In this proposed design, natural gas is introduced along with the air via the conventional side air intake and natural gas or a mixture of natural gas and air is introduced through a peripheral intake just downstream of the conventional air intake. However, with such engines, it is believed that the gaseous fuel would be concentrated in the trailing portion of the combustion chamber. This leads to flame quenching and leakage, resulting in reduced efficiency and high hydrocarbon emissions.